LTC4214-2_15 Datasheet, PDF (1/32 Pages) Linear Technology – Negative Low Voltage Hot Swap Controllers

FEATURES
s _{Allows Safe Board Insertion and Removal from a}
Live Backplane
s _{Controls Supplies from 0V to –16V}
s _{Adjustable Analog Current Limit With Circuit}
Breaker Timer
s _{Fast Response Time Limits Peak Fault Current}
s _{Adjustable Soft-Start Current Limit}
s _{Adjustable Timer with Drain Voltage Accelerated}
Response
s _{Adjustable Undervoltage/Overvoltage Protection}
s _{LTC4214-1: Latch Off After Fault}
s _{LTC4214-2: Automatic Retry After Fault}
s _{Available in the 10-Pin MSOP Package}
U
APPLICATIO S
s _{Hot Board Insertion}
s _{Electronic Circuit Breaker}
s _{Negative Power Supply Control}
s _{Central Office Switching}
s _{High Availability Servers}
s _{Disk Arrays}
s _{Optical Networking/Switching}
s _ECL
LTC4214-1/LTC4214-2
Negative Low Voltage
Hot Swap Controllers
DESCRIPTIO
The LTC^®4214 negative voltage Hot Swap^TM controller
allows a board to be safely inserted and removed from a
live backplane. Output current is controlled by three stages
of current limiting: a timed circuit breaker, active current
limiting and a fast feedforward path that limits peak
current under worst-case catastrophic fault conditions.
Adjustable undervoltage and overvoltage detectors dis-
connect the load whenever the input supply exceeds the
desired operating range. The LTC4214 controls negative
supplies ranging from near zero to –16V. A multifunction
timer delays initial start-up and controls the circuit breaker’s
response time. This response time is accelerated by
sensing excessive MOSFET drain voltage, keeping the
MOSFET within its safe operating area (SOA). An adjust-
able soft-start circuit controls MOSFET inrush current at
start-up. A power good status output can enable a power
module at start-up or disable it if the circuit breaker trips.
The LTC4214-1 latches off after a circuit breaker fault times
out. The LTC4214-2 provides automatic retry after a fault.
The LTC4214 is available in the 10-pin MSOP package.
, LTC and LT are registered trademarks of Linear Technology Corporation.
Hot Swap is a trademark of Linear Technology Corporation.
TYPICAL APPLICATIO
3.3V
GND
10Ω
100nF
GND
(SHORT PIN)
34k
1%
32.4k
1%
–5.2V
– 5.2V/5A ECL Supply Hot Swap Controller
2k
SMAJ7A
5.6nF
1nF PUSH
RESET
470Ω
1
V_IN
LTC4214-1 ₂
PWRGD
9, 8 _UV/OV
7
DRAIN
10
6
TIMER GATE
3
SS
4
SENSE
V_EE
5
3.3nF
0.1µF
22Ω
EN
BSS138
C_LOAD ⁺
100µF
GND
–5.2V
ECL
75k
IRF7413
10Ω
10nF
0.01Ω
4214 TA01
GATE
5V/DIV
SENSE
20mV/DIV
V_OUT
5V/DIV
PWRGD
5V/DIV
Start-Up Behavior
4214 TA02
421412f
1